IIRC the only gears offered in a 2nd gen was 3.54's and 4.10's

no factory 3.73's in a diesel.

 

thats right

 

What is the disadvantage of putting stiffer springs in? Cost, lower MPG, higher idle speed??

 

the cost is cheep, your mpg should stay the same after you keep your foot out of it, the idle speed should go up but there is and adjustment for that.

the only disadvantage would be .... you will soon need a new clutch due to the added low and top end fueling.

 

Why not just buy some decent springs, locks, and retainers from Summit Racing, 160lbs on the seat, what they should be. 60lb springs were designed to be used with an exhaust brake, not to handle increased RPM and lift.

 

Specs to look for weston?

 

i once hit 4100 rpm's while free reving my truck with stock valve springs, keepers and retainers. this was with wayyyyy to much alcohol tho and would NOT recomend tryin it. haha idk how i didnt float a valve or mess my valvetrain up. but i consider myself lucky, very lucky